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Diffstat (limited to 'arch/mips/kernel/signal.c')
-rw-r--r--arch/mips/kernel/signal.c136
1 files changed, 110 insertions, 26 deletions
diff --git a/arch/mips/kernel/signal.c b/arch/mips/kernel/signal.c
index b2e9ab1bb101..07d67309451a 100644
--- a/arch/mips/kernel/signal.c
+++ b/arch/mips/kernel/signal.c
@@ -20,6 +20,7 @@
#include <linux/ptrace.h>
#include <linux/unistd.h>
#include <linux/compiler.h>
+#include <linux/uaccess.h>
#include <asm/abi.h>
#include <asm/asm.h>
@@ -27,7 +28,6 @@
#include <asm/cacheflush.h>
#include <asm/fpu.h>
#include <asm/sim.h>
-#include <asm/uaccess.h>
#include <asm/ucontext.h>
#include <asm/cpu-features.h>
#include <asm/war.h>
@@ -78,10 +78,51 @@ struct rt_sigframe {
/*
* Helper routines
*/
+static int protected_save_fp_context(struct sigcontext __user *sc)
+{
+ int err;
+ while (1) {
+ lock_fpu_owner();
+ own_fpu_inatomic(1);
+ err = save_fp_context(sc); /* this might fail */
+ unlock_fpu_owner();
+ if (likely(!err))
+ break;
+ /* touch the sigcontext and try again */
+ err = __put_user(0, &sc->sc_fpregs[0]) |
+ __put_user(0, &sc->sc_fpregs[31]) |
+ __put_user(0, &sc->sc_fpc_csr);
+ if (err)
+ break; /* really bad sigcontext */
+ }
+ return err;
+}
+
+static int protected_restore_fp_context(struct sigcontext __user *sc)
+{
+ int err, tmp;
+ while (1) {
+ lock_fpu_owner();
+ own_fpu_inatomic(0);
+ err = restore_fp_context(sc); /* this might fail */
+ unlock_fpu_owner();
+ if (likely(!err))
+ break;
+ /* touch the sigcontext and try again */
+ err = __get_user(tmp, &sc->sc_fpregs[0]) |
+ __get_user(tmp, &sc->sc_fpregs[31]) |
+ __get_user(tmp, &sc->sc_fpc_csr);
+ if (err)
+ break; /* really bad sigcontext */
+ }
+ return err;
+}
+
int setup_sigcontext(struct pt_regs *regs, struct sigcontext __user *sc)
{
int err = 0;
int i;
+ unsigned int used_math;
err |= __put_user(regs->cp0_epc, &sc->sc_pc);
@@ -89,6 +130,9 @@ int setup_sigcontext(struct pt_regs *regs, struct sigcontext __user *sc)
for (i = 1; i < 32; i++)
err |= __put_user(regs->regs[i], &sc->sc_regs[i]);
+#ifdef CONFIG_CPU_HAS_SMARTMIPS
+ err |= __put_user(regs->acx, &sc->sc_acx);
+#endif
err |= __put_user(regs->hi, &sc->sc_mdhi);
err |= __put_user(regs->lo, &sc->sc_mdlo);
if (cpu_has_dsp) {
@@ -101,24 +145,48 @@ int setup_sigcontext(struct pt_regs *regs, struct sigcontext __user *sc)
err |= __put_user(rddsp(DSP_MASK), &sc->sc_dsp);
}
- err |= __put_user(!!used_math(), &sc->sc_used_math);
+ used_math = !!used_math();
+ err |= __put_user(used_math, &sc->sc_used_math);
- if (used_math()) {
+ if (used_math) {
/*
* Save FPU state to signal context. Signal handler
* will "inherit" current FPU state.
*/
- preempt_disable();
+ err |= protected_save_fp_context(sc);
+ }
+ return err;
+}
- if (!is_fpu_owner()) {
- own_fpu();
- restore_fp(current);
- }
- err |= save_fp_context(sc);
+int fpcsr_pending(unsigned int __user *fpcsr)
+{
+ int err, sig = 0;
+ unsigned int csr, enabled;
- preempt_enable();
+ err = __get_user(csr, fpcsr);
+ enabled = FPU_CSR_UNI_X | ((csr & FPU_CSR_ALL_E) << 5);
+ /*
+ * If the signal handler set some FPU exceptions, clear it and
+ * send SIGFPE.
+ */
+ if (csr & enabled) {
+ csr &= ~enabled;
+ err |= __put_user(csr, fpcsr);
+ sig = SIGFPE;
}
- return err;
+ return err ?: sig;
+}
+
+static int
+check_and_restore_fp_context(struct sigcontext __user *sc)
+{
+ int err, sig;
+
+ err = sig = fpcsr_pending(&sc->sc_fpc_csr);
+ if (err > 0)
+ err = 0;
+ err |= protected_restore_fp_context(sc);
+ return err ?: sig;
}
int restore_sigcontext(struct pt_regs *regs, struct sigcontext __user *sc)
@@ -132,6 +200,10 @@ int restore_sigcontext(struct pt_regs *regs, struct sigcontext __user *sc)
current_thread_info()->restart_block.fn = do_no_restart_syscall;
err |= __get_user(regs->cp0_epc, &sc->sc_pc);
+
+#ifdef CONFIG_CPU_HAS_SMARTMIPS
+ err |= __get_user(regs->acx, &sc->sc_acx);
+#endif
err |= __get_user(regs->hi, &sc->sc_mdhi);
err |= __get_user(regs->lo, &sc->sc_mdlo);
if (cpu_has_dsp) {
@@ -150,19 +222,15 @@ int restore_sigcontext(struct pt_regs *regs, struct sigcontext __user *sc)
err |= __get_user(used_math, &sc->sc_used_math);
conditional_used_math(used_math);
- preempt_disable();
-
- if (used_math()) {
+ if (used_math) {
/* restore fpu context if we have used it before */
- own_fpu();
- err |= restore_fp_context(sc);
+ if (!err)
+ err = check_and_restore_fp_context(sc);
} else {
/* signal handler may have used FPU. Give it up. */
- lose_fpu();
+ lose_fpu(0);
}
- preempt_enable();
-
return err;
}
@@ -325,6 +393,7 @@ asmlinkage void sys_sigreturn(nabi_no_regargs struct pt_regs regs)
{
struct sigframe __user *frame;
sigset_t blocked;
+ int sig;
frame = (struct sigframe __user *) regs.regs[29];
if (!access_ok(VERIFY_READ, frame, sizeof(*frame)))
@@ -338,8 +407,11 @@ asmlinkage void sys_sigreturn(nabi_no_regargs struct pt_regs regs)
recalc_sigpending();
spin_unlock_irq(&current->sighand->siglock);
- if (restore_sigcontext(&regs, &frame->sf_sc))
+ sig = restore_sigcontext(&regs, &frame->sf_sc);
+ if (sig < 0)
goto badframe;
+ else if (sig)
+ force_sig(sig, current);
/*
* Don't let your children do this ...
@@ -361,6 +433,7 @@ asmlinkage void sys_rt_sigreturn(nabi_no_regargs struct pt_regs regs)
struct rt_sigframe __user *frame;
sigset_t set;
stack_t st;
+ int sig;
frame = (struct rt_sigframe __user *) regs.regs[29];
if (!access_ok(VERIFY_READ, frame, sizeof(*frame)))
@@ -374,8 +447,11 @@ asmlinkage void sys_rt_sigreturn(nabi_no_regargs struct pt_regs regs)
recalc_sigpending();
spin_unlock_irq(&current->sighand->siglock);
- if (restore_sigcontext(&regs, &frame->rs_uc.uc_mcontext))
+ sig = restore_sigcontext(&regs, &frame->rs_uc.uc_mcontext);
+ if (sig < 0)
goto badframe;
+ else if (sig)
+ force_sig(sig, current);
if (__copy_from_user(&st, &frame->rs_uc.uc_stack, sizeof(st)))
goto badframe;
@@ -398,7 +474,7 @@ badframe:
}
#ifdef CONFIG_TRAD_SIGNALS
-int setup_frame(struct k_sigaction * ka, struct pt_regs *regs,
+static int setup_frame(struct k_sigaction * ka, struct pt_regs *regs,
int signr, sigset_t *set)
{
struct sigframe __user *frame;
@@ -443,7 +519,7 @@ give_sigsegv:
}
#endif
-int setup_rt_frame(struct k_sigaction * ka, struct pt_regs *regs,
+static int setup_rt_frame(struct k_sigaction * ka, struct pt_regs *regs,
int signr, sigset_t *set, siginfo_t *info)
{
struct rt_sigframe __user *frame;
@@ -501,6 +577,14 @@ give_sigsegv:
return -EFAULT;
}
+struct mips_abi mips_abi = {
+#ifdef CONFIG_TRAD_SIGNALS
+ .setup_frame = setup_frame,
+#endif
+ .setup_rt_frame = setup_rt_frame,
+ .restart = __NR_restart_syscall
+};
+
static int handle_signal(unsigned long sig, siginfo_t *info,
struct k_sigaction *ka, sigset_t *oldset, struct pt_regs *regs)
{
@@ -539,7 +623,7 @@ static int handle_signal(unsigned long sig, siginfo_t *info,
return ret;
}
-void do_signal(struct pt_regs *regs)
+static void do_signal(struct pt_regs *regs)
{
struct k_sigaction ka;
sigset_t *oldset;
@@ -589,7 +673,7 @@ void do_signal(struct pt_regs *regs)
regs->cp0_epc -= 8;
}
if (regs->regs[2] == ERESTART_RESTARTBLOCK) {
- regs->regs[2] = __NR_restart_syscall;
+ regs->regs[2] = current->thread.abi->restart;
regs->regs[7] = regs->regs[26];
regs->cp0_epc -= 4;
}
@@ -615,5 +699,5 @@ asmlinkage void do_notify_resume(struct pt_regs *regs, void *unused,
{
/* deal with pending signal delivery */
if (thread_info_flags & (_TIF_SIGPENDING | _TIF_RESTORE_SIGMASK))
- current->thread.abi->do_signal(regs);
+ do_signal(regs);
}
generated by cgit v1.2.3 (git 2.0.4) at 2024-11-05 10:08:55 +0000